Apple on Tuesday seeded a fresh OS X 10.8.3 Mountain Lion beta to developers and Apple Seed participants, asking testers to focus on AirPlay, Graphics Drivers and other areas while further detailing the new Software Update feature for pre-release builds.

A little over one week after Apple seeded build 12D32 of its OS X 10.8.3 beta to developers, the company has rolled out another version of the software adding a new functionality that allows developers to download and install pre-release versions directly from Software Update in the Mac App Store.